SNAKES OF CEYLON. - 517 



physician's mind the identical state of affairs one sees in 

 Henoch's purpura. Similarly, there may be extravasations 

 into joints, or other serous cavities, which may become 

 painful and swollen, reminding one of another clinical con- 

 dition, viz., arthritic purpura. Hemorrhages are apt to 

 occur under the skin, producing port wine discolourations in 

 the form of spots or patches Of various sizes, or they may 

 occur in muscles and other tissues, giving rise to painful and 

 tender swellings. 



Death due to cardiac failure, induced by toxins (1) (a) and 

 (4), or later on to exhaustion, may occur in from 1 to 14 days, 

 or even longer. 



(k) Symptoms : Daboia poisoning may be taken as the 

 type of Viperine toxaemias. 



Experimentally in animals three forms of toxeemise are 

 observed. 



It was observed by A. J. Wall, Fayrer, and others experi- 

 menting on animals that when the dose of poison was large, 

 rapid and violent convulsions were induced, resulting in death 

 from asphyxia in a few seconds or minutes. Lamb was the 

 first to correctly interpret these phenomena. He found that 

 daboia venom contains a ferment that coagulates blood. 

 This ferment is only operative in highly concentrated doses of 

 poison. It causes clotting of blood inside the blood vessels, 

 and to this is attributable the convulsive seizure and death 

 from asphyxia. He further showed that the dose necessary 

 is so large that it is very unlikely that this mode of death 

 would ever be seen in the human subject. 



The other two forms of toxsemise, one acute the other sub- 

 acute or chronic, are to be met with in the human subject. 

 In the acute form there is general depression, in which the 

 vital functions connected with both the heart and respiration 

 are profoundly affected. The pulse becomes rapid and weak, 

 and breathing rapid and irregular. General weakness of the 

 muscular system is seen, and the mental activities may be 

 reduced to the degree of unconsciousness. Nausea and 

 vomiting are frequent, and the pupils become dilated and 

 insensitive to light. The surface temperature is reduced, and 



